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Tapping Noise after timing belt..

5K views 13 replies 4 participants last post by  eGoCeNTRoNiX 
#1 ·
Hello All,

Symptoms :

Almost done with the timing belt change, I have everything bolted back up and all that really remains is to hook up the radiator lines to the new radiator, ran out of day light last night. I was able to start her successfully, but with one concern. There is a random, not consistent, loud tapping noise. It's not the same noise that you hear from lifters. I haven't let the engine run for more than about 20 seconds as I was worried about the noise. But it starts and revs up to about 2k and doesn't feel like it's missing or anything, actually feels like it's running very smooth for it's normal warm up.

Findings :

I have a feeling it's the timing cover. I did some googling of my issue and found an instance where somebody (totally different car) also had a tapping noise. And it ended up that the timing cover was lose. Well, when I was taking the timing cover off, I found that one of the bolts had the head twisted off of it at some point in time on the upper cover. And on the bottom cover, the very bottom bolt under the crank pulley, the part of the engine that the cover bolts into had cracked off and came up with the timing cover. It was pretty dirty, so I assumed it had been broken for some time. I'm at the point now, where I feel like I should go and pick up a longer bolt to use in that location and try to figure out how to get the broken one out of it's spot. I will try to get a video of the noise tonight when I get home.

Does anybody have any ideas, or does it sound like I'm on the right track? I just don't want to hurt anything.

TIA!

eGo
 
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#3 ·
I didn't have the same sound issue as you, but I did manage to put one of the regular cover bolots in the spot behind the crank pulley rather than the bolt without the rubber gasket thingy. Fired it up and had one hell of a squeal. One reason maybe to not do it later at night as I had to rip it all back apart just to change that bolt!
 
#4 ·
I didn't have the same sound issue as you, but I did manage to put one of the regular cover bolots in the spot behind the crank pulley rather than the bolt without the rubber gasket thingy. Fired it up and had one hell of a squeal. One reason maybe to not do it later at night as I had to rip it all back apart just to change that bolt!
Well, I put the timing cover on during the day.. The stuff I was putting back on at night were the pulleys/belts and what not. But, there are two spots where the bolt is either missing or the casing is broken. Where the bolt head snapped off, I'm hoping I can use an easy out/rescue bit and get it out and put another one in it's place. For the very bottom one, the part of the engine casing where it attaches broke off so there is no way for me to get this bolt to attach. At least not without replacing something. So not really sure what to do here if this is the part that's making the tapping noise.. ;\

eGo
 
#5 ·
My lowest mount also busted off the engine, but didn't cause any problems until I tried to remove the crank pulley. After that the lower cover would tap against the pulley. I wound up having my shop grind off the lowest tab off the cover and it's quiet now. Until I got to that point, I had to tie back the cover, doing so by looping some wire around the lowest point of the cover and tying it back to the transmission cooler lines.
 
#6 ·
My lowest mount also busted off the engine, but didn't cause any problems until I tried to remove the crank pulley. After that the lower cover would tap against the pulley. I wound up having my shop grind off the lowest tab off the cover and it's quiet now. Until I got to that point, I had to tie back the cover, doing so by looping some wire around the lowest point of the cover and tying it back to the transmission cooler lines.
I'm happy to know I'm not the only one who experienced this problem!! I may try to tie it back, or I may just cut it off with my dremel.. Although, at this point it's going to have to be tied back until I rent the pulley puller tool again.. lol Thanks for the info, greatly appreciated! :) I'll let you know how it turns out when I get a chance to mess with it. Probably won't be until Sunday.

eGo
 
#7 ·
Ok.. So, back to this.. Image below.. This is the mount that is broken.. I looked around and I couldn't find any place I felt safe tying it back to, but I do have some steel wire. My main concern is the wire breaking and ending up tangled around all of the belts/pulleys. This is my wife's truck and she will be the one driving it most of the time. What are the down sides to removing the lower timing cover and leaving it off? Has anybody done this? We don't use it for off road purposes right now. I'd really like to know if there's an easy way to fix this. I can push the piece back in place and it will stay, but as soon as I start the truck it pops loose again. I'd really really like to be able to put this thing back together and be done with it. I've got some other projects I need to focus on.. :( Any and all ideas are welcome!

eGo

 
#8 ·
Maybe it's not the culprit.. I just started the car without the crank pulley on and it is still tapping, I hadn't ever gotten out of the car to check. Is it possible my timing is off? What else could be causing this? I did change the driver's side valve cover gasket during this process. Do I need to tear the covers off and recheck the timing?

TIA!

eGo
 
#9 ·
I took the timing covers back off.. I have 40 teeth between the LH and RH timing marks at the cams, but I'm well over 43 between the LH Cam and the timing mark on the crankshaft timing mark.. I'm assuming that I need to work on getting the right number of teeth between them. So I will work on that in the morning. The flies/mosquitoes are too bad right now to keep going for the night. I just hope I haven't messed anything up. If anybody could chime in with any suggestions on getting things lined up, I'd appreciate it.

eGo
 
#10 ·
My main concern is the wire breaking and ending up tangled around all of the belts/pulleys. This is my wife's truck and she will be the one driving it most of the time. What are the down sides to removing the lower timing cover and leaving it off? Has anybody done this?
I had mine tied off only so I could make it to my mechanic without fearing the lower cover grinding off part of the pulley. I currently run WITHOUT a lower mount (cover is on)
 
#11 ·
Hoping to get to this next weekend, this weekend is going to be too damned busy.. At this point I'm wondering if it's possible that something got messed up in the driver side head... Or if the timing is off as mentioned before. Can anybody tell me if the tooth count between the LH Cam sprocket and the crank sprocket is supposed to be from mark to mark or ??

TIA!!

eGo
 
#12 ·
Well.. Finally done.. Car is running nicely now.. Still taps a little on startup, but the valve lifters straightened themselves out.. So now I have a full set for sale if anybody needs them.. $80 shipped anywhere in the US. Was low on tranny fluid, going out to top it off now and take it for a spin.. Thank you all for your help.

eGo
 
#13 ·
So you got new lifters or what? My 04 is making that sound, especially when colder and /or excellerating. I thought it was media rattling in the cats since im getting cat codes.Havent found anything touching moving parts under the hood or truck. My motor just got installed a couple weeks ago. I seafoamed and modded the intake and truck runs, idles, smooth. good gas milage. this noise drivin me crazy. Was it the timing for you or valve adjustment? I dont see your post of how you fixed it, just that it (the valves) worked themselves out.
 
#14 ·
I did not replace the valve lifters.. I have 12 brand new ones waiting to be sold.. haha.. But, in response to your question, I didn't do anything to them, just letting the engine run for 2-3 minutes allowed the lifters to fill up and smooth out, then the noise went away.
 
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